Simulation of Assembly Tolerance and Characteristics of High Pressure Common Rail Injector

Abstract

Fuel injector is the key part of a high-pressure common rail fuel injection system. Its manufacturing precision and assembly quality affect system's property and performance. According to the characteristics and demands of assembly of the fuel injector, an intelligent optimization algorithm is proposed to resolve the problem of assembly sequence planning. Based on geometric modeling, assembly dimension chain of the injector control chamber is established, and the relationship between assembly tolerance and volume change of control chamber is analyzed. The optimization model of the assembly is established. The impact of assembly tolerance on injector's performance is simulated according to the optimization algorithm. The simulation result shows that quantity of injection fuel changes correspondingly with the change of assembly tolerance, while injection rate and pressure do not change significantly, and the response rate of needle considerably slow. Similarly, the leakage rate of fuel in control chamber is calculated, indicating that the assembly tolerance has obvious impact on fuel leakage and its rate. The study illuminates that injector's assembly tolerance has prominent effect on injection.

Modeling Of Hydrodynamic Processes in Diesel Injector Nozzle

“…Given the trends in the automotive industry, today it is necessary to have a resource of about 500 thousand km. It gives to designer the task of increasing the reliability of the most vulnerable elements of the diesel injectors: friction pairs, injector cone seat, nozzle holes and injector nozzle tip [1][2][3][4][5].…”

Study on the leakage of plunger pair under static condition in high-pressure common rail injector considering deformation effect

“…1,2 As a precise structure, the plunger pair is one of the parts which mostly malfunction in the injector. 3 The poor sealing performance of the plunger pair results in slow response of the injector, for example bad nebulization effect, which reduces engine burning efficiency. So, it is necessary to study on the sealing performance of plunger pair.…”

Modeling of Processes Into Electro-Hydraulic Valves of an Engine’ Fuel System

“…The computational study has been performed in a multi-hole nozzle at ten different fixed needle lifts, cavitation modelling with a continuous flow in the nozzle model that considers the cavitating nozzle flow as a homogeneous mixture of liquid and vapor, and taking into account the turbulence effects [13][14][15]. Based on the geometric modelling, assembly the dimension chain of the injector control chamber is established, and the relationship between the assembly tolerance and volume change of the control chamber is analyzed [16]. The simulation result shows that the volume of fuel injection changes correspondingly with a change of the assembly tolerance, while injection rate and pressure do not change significantly and the response rate of the needle is considerably slow.…”